Formation of the TNC effectively suspends Guinea-Bissau's constitution.
The announcement about the council's formation came after a group of 22 mostly opposition political parties met with military leaders Sunday, CNN reported.
TNC spokesman Fernando Vaz said the makeup of the council would be determined after a meeting Monday.
The council president will serve as the country's interim president until elections are conducted, Vaz said.
Members of the TNC's diplomatic panel were to meet with representatives of the Economic Community of West African States Monday, CNN said.
The regional organization said in a statement it has "zero tolerance for power obtained by unconstitutional means."
"The delegation will reaffirm ECOWAS' rejection of the coup, which has been widely condemned by the international community ... and impress on the junta to restore constitutional rule immediately," the group said.
World leaders have denounced last week's coup that occurred just before a second round of presidential elections scheduled for April 29. Soldiers took Acting President Raimundo Pereira and Prime Minister Carlos Gomes Jr. into custody Thursday.
Daba Naualna, a spokesman for the army's chief of staff, said Pereira and Gomes were alive. He said leaders of the nation's military took control of Guinea-Bissau ensure stability, CNN reported.
"The [army chief of staff] thinks, for the sake of the country, that power cannot fall into the streets and decided to have [the military] play its part in seeking solutions with the political class to resolve this crisis," Naualna said.
On Sunday, the military command said Guinea-Bissau was closed to air traffic and maritime traffic from abroad as a matter of national security.